Boats with skin or skin-like hulls have been made and used from before recorded history in North America and other areas of the world. In North America, these range from the usually umbrella-or hemispherically-shaped bull boats of the Plains Indians, constructed from buffalo skins stretched over a framework of saplings, or the skin of moose stretched over a rowboat-like framework of small trees by Indians of Athabascan stock in Northwestern Canada, to kayaks made from walrus skins stretched over whale rib bones by Eskimos of the polar regions. Folding boats have been patented on both the North American and Eurasian Continent for more than a century. Although at least one commercially successful folding canoe is on the market, most commercially successful folding watercraft are kayaks.
Open canoes and kayaks represent the extreme ends of a range or continuum of hull forms. The open canoe's hull is open all along the top, while the hull of the kayak completely envelopes the craft except for the cockpit opening of the paddler. In the middle of this range, canoes and kayaks are difficult to distinguish from each other. Since the middle of this century, some canoes have been fitted with a cover or a deck of rigid material, as an integral part of the canoe, making them difficult to distinguish from kayaks. This is particularly true of slalom racing canoes and kayaks.
For an observer, the method of propulsion and posture of the paddler in the boat is the most reliable indication of whether the boat is a canoe or a kayak. The primary method of propulsion of a canoe is by a single-bladed paddle with the canoeist either sitting erect with feet flat on the floor ahead of the paddler or tucked beneath or beside the paddler's seat. The primary method of propulsion of a kayak is through use of a double-bladed paddle with the kayaker sitting close to or on the floor of the kayak with feet and legs extended in front. A solo canoeist may choose to use a double bladed paddle at times with increased paddling comfort and effectiveness on flat water, but conversely, it is anatomically difficult to use a single-bladed paddle and be effective at propelling a kayak.
Rowboats present a different type of craft primarily in the way in which they are propelled. They are equipped with oar-locks and use oars. However, many canoes are rigged for rowing as are some types of kayaks. So the distinction here is again one more of posture of the paddler or rower than the boat itself as to how to classify it.
Mimicking the general design of the native North American birchbark canoes, modern open canoes are structured using a watertight skin covering that can be either rigid, semi-rigid or flexible as one of the components of the hull. The definition of the hull is somewhat arbitrary but is presumed to be the entire structure exclusive of the seats, thwarts, gunwales, and other things which are detachable from the craft. It is normally considered to comprise two parts, a skeletal structure inside to create hull rigidity, and a covering over it to keep the water out, i.e., the skeleton and the skin. It may or may not contain longitudinal ribs called stringers in a folding canoe, and cross-ribs called formers in a folding canoe, depending on the stiffness, strength, and rigidity of the skin.
If the hull skin is pre-formed and of sufficient strength and stiffness, it may contain no skeleton. Examples of this are open canoes made of a heat formed laminate referred to by brand names as Royalex or Oltonar, and of plastics such as cross-linked polyethylene. If the skin of an open boat is a fabric coated for abrasion resistance and waterproofness, such as canvas, or is made of aluminum, or fiberglass, it will more often contain a skeleton to give shape and rigidity to the hull in open boats.
However, in most open boats horizontal transverse members called thwarts are present which attach between opposing gunwales to maintain the transverse spacing of the gunwales and provide lateral strength to the boat and assist in maintaining the overall shape and rigidity of the hull.
At least one inflatable open canoe containing no solid rigid members anywhere in its structure is commercially available, but it has the serious disadvantage of being heavy, about half again or twice as heavy as the present invention of an equivalent size and load-carrying capacity, and it is not comfortable to be in for long periods of time. Many brand names and models of inflatable kayaks currently on the market, best know to laypersons as "rubber duckies", likewise aren't well- suited for use for long periods of time. The problem with these self-bailing inflatables is that the seat is too close to the floor for proper sitting comfort hour after hour. An inefficient and anatomically uncomfortable paddling position while sitting is the trade-off for achieving a self-bailing canoe.
The established advantages of flexible canoes are primarily advantages relative to hard-hulled boats. They are as follows:
1) Light weight. PA1 2) Soft hull which reduces damage to other equipment such as car or truck roofs when transporting. PA1 3) Soft hull and fewer exposed hard surfaces or fittings to cause damage to hands, fingers, toes or other limbs if the craft is accidentally dropped. PA1 4) Easily transportable and easily stored in minimal space. PA1 5) Packaging capability facilitates commercial transport on public transportation such as buses, trains and airplanes. PA1 6) Hull skin materials provide insulation from cold water. PA1 7) Soft skinned hull material is the quietest of all materials when scraping or bumping rocks or other below or above water solid objects. PA1 8) When the boat is pinned in a broach situation, the flexibility of the hull provides greater capability to free the craft from the pinned position than that of hard hulled boats. PA1 9) A person pinned and trapped by the boat, in a potentially life or bodily harm threatening situation, may more readily be freed by the ability of the hull skin material to be cut with an ordinary knife increasing the chance of freeing the victim. With hard hulled boats this potential is minimal or does not exist. PA1 10) The lightness, and the softness of the hull materials of a flexible boat make it easier to manage and recover by a swimmer in a capsize situation. This is particularly advantageous when capsized in a rapids. It reduces the chance of injury because of the absence of hard inflexible surfaces such as are present in hard-hulled boats. PA1 11) The hull yields under shock, which may reduce damage to it, and which allows improved control in turbulent water. PA1 12) The flexibility in the hull assists in maintaining a drier boat, i.e., it ships less water, by somewhat conforming to the shape of waves rather than slicing through them. PA1 13) A folding canoe has the advantage over other folding craft such as kayaks of remaining assembled for the duration of the paddling season, stored, and used like any other canoe. It provides a less expensive transport solution for day trips. It is transportable as are other canoes by means of inverting it over a pair of straight barred roof racks and tied down without requiring disassembly of the boat. Specially built roof rack adapters are not required. It can, as other folding craft such as canoes and kayaks, be checked as extra luggage on commercial air flights.
Shortcomings of the current state of the art of commercially successful collapsible boats using internal framework with a flexible hull skin are best understood by the currently most successful of these, the folding canoes disclosed by Jensen in U.S. Pat. No. 4,290,157. Other folding canoes which exist or have been attempted are similar to the Jensen technology. The three principal problems cited by users of these craft, which are each major problems, built using this technology are 1) the hull has too much flex in it, 2) the skeleton is not structurally sound, and 3) the canoe becomes heavy and unmanageable in use by water getting trapped under the floor foam. Other problems of a more peripheral nature, also present, will be discussed hereinbelow.
As noted, structural rigidity remains a problem in the prior art. If, in an otherwise empty canoe, a solo paddler sits in the middle, the ends rise out of the water creating more rocker. The hull acquires convex flex. It's shape becomes that of a banana boat, a term given to highly rockered canoes. It makes the boat highly maneuverable, i.e., easy to turn. If two tandem paddlers sit at the ends of the boat, one at each end, the center of the boat rises as the ends sink deeper into the water creating an concave hull with inverse rocker, like an upside down banana, which makes the boat less maneuverable. This creates boat handling problems and is not conducive to continued structural integrity of the canoe in turbulent water conditions. Limited flexibility is an advantage, too much flexibility is a disadvantage. To date no-one has been able to strike the necessary balance.
Moreover, the longer the canoe the more pronounced the problem. It becomes significantly noticeable in the 15 foot model but becomes a problem in the 16.5 foot model for both a solo paddler positioned at the center of the canoe and for tandem paddlers positioned toward the ends of the canoe. In the 18 foot model it is a serious problem, which, when taken together with the other structural problems present in the prior art, compromises the viability of these longer canoes with experienced whitewater and wilderness paddlers. The hulls are too flexible in the longitudinal direction limiting maneuverability and contributing to poorer structural integrity.
Part of this problem is obvious and part is not obvious. The obvious part is when a paddler's foot, while seeking a secure hold in the bottom of the canoe, presses against the cross-rib or former, it can become dislodged from its placement within the skeletal structure. A user solution to this common problem is to reinforce the connections with segments of nylon cord tied around the stringers and formers where they intersect. The other problem is the lack of a secure connection of the former to the gunwale. The design of both the connector fastening the former to the floor stringers and with the connectors which fasten the former to the gunwale has not provided for effective security. Neither are secure connections. These connector designs often require multiple attempts for successful assembly by the user at the onset of a trip.
In addition, the structural tubular frame skeleton of the canoe is not self-supporting and relies on interaction with the hull skin to maintain structural integrity, and often partially disassembles in actual field use and abuse, which is typical of the conditions to which such craft are exposed. The need to lock gunwales to the formers is not obvious because in, e.g., the Jensen design, the hull skin is an integral component in the system to maintain skeletal integrity. The compression placed downward on the gunwale connectors by the skin via the gunwales is critical, by design, or otherwise, to maintain the connectors in place on the gunwales.
This reliance on tension in the skin, to maintain structural integrity of the skeleton, is a problem which needs to be solved if structural integrity is to be maintained during operational conditions which cause mechanical stress on the canoe, i.e., either from the hydraulic action of water in a swamped and out-of-control canoe, a boat rescue situation after a capsize, a canoe's being pinned or broached on some in-stream obstruction, or a water laden canoe being maneuvered down a rapids, bumping and scraping underwater obstructions.
Water entrapment under the foam floor causes increased weight and loss of operational maneuverability and manageability, and is an ever-present problem in prior art designs. The foam in the floor of the canoe is not attached to or otherwise integrated with the hull skin which causes water to creep under the foam and the fabric, making the canoe heavier, more difficult to maneuver, and more likely to disassemble in use because of the above-stated problems with its skeleton. Having that happen in the middle of a raging rapids, with a boat laden with camping gear miles from the nearest road, may be dangerous to the occupants of the canoe. It is annoying to a day use recreational paddler.
Other problems which are important but not as serious are: a) the foam in the bottom of the boat rather than on the sides makes it more difficult to upright a capsized boat. It is of marginal value when trying to maintain control of a swamped boat and may actually hamper such efforts because of its position placement in the canoe, b) gunwale terminators and connectors consist of too many small easy-to-misplace parts, c) in spite of claims to the contrary, a rubber hammer and small wrench are required to assemble and maintain an assembled canoe, and d) the seat does not fold nor easily accommodate a kneeling paddler, and e) there is no carrying or portage yoke system available.
As is clear from the above, to date, in spite of their numerous advantages over hard-hulled craft, and although adequate to serve the general purposes they were designed for, most folding watercraft still do not have sufficient credibility among experienced users to become a major contender as a boat of choice.
When considering boats with flexible hull skins, post the era of the aboriginal skin boats, collapsible boats, comprising stringers, formers, a keel and gunwales in various arrangements in sectional break down form, have a rich history. This is particularly true in North America around the turn of the last century and later in this century. Portable, collapsible, or folding boats disclosed in U.S. Pat. Nos. 598,989, 833.846, and 2,053,755 have had shortcomings such as a keel made specifically of gas pipe, too many loose parts, easy-to-lose small parts, complicated rib connections with ferrules and auxiliary ribs. All are time consuming to assemble. More recently a kayak disclosed in U.S. Pat. No. 3,869,743 uses a sliding fastener as a means to insert the skeleton into the hull skin. It boat does not implement hull-flex reduction measures.
Some of the collapsible boats use air sponsons or air bladders in the sides. An early boat disclosed in U.S. Pat. No. 507,439 suffers the usual shortcomings of too many parts to lose and features air sponsons in the floor and sides with no claims and no description of function or purpose for them. A collapsible boat disclosed in U.S. Pat. No. 2,338,976 uses air sponsons in the sides of the hull for tensioning the skin, for flotation, and for transverse shock absorption. The hull stiffening comes from the skeletal structure alone in the description. A rowboat and motorboat are described. Focusing on preventing securing joints for connecting side sponsons from disintegrating in collapsible kayaks, it is disclosed in U.S. Pat. No. 3,049,731 how to secure a single-chambered sponson to the each side by suspension from the deck. It does not mention the purpose of the sponsons. A challenge craft disclosed in U.S. Pat. No 4,961,397 employs sponsons for skin tensioning but makes a questionable claim that the sponsons contribute to craft stability. In a collapsible canoe disclosed in U.S. Pat. No. 4,751,889, air sponsons, in the side, are stated to be for the purposes of skin tensioning and buoyancy.
As can be seen, therefore in the prior art no disclosure has been made of air sponsons or bladders being used to serve the purpose of reducing flex in the hull for increased boat handling performance in collapsible, or folding boats, containing an internal hull-shaping skeletal framework.
In a collapsible boat design, disclosed in U.S. Pat. No. 3,070,816, a gunwale terminator is present integrated into the skeletal structure by a specific fastening system. However, the formers are mounted to the gunwales without a fastening device to lock the two together.
A fastener or buckle, disclosed in U. S. Pat. No. 5,311,649, used commonly for securing straps on backpacks and belts and similar devices, requires two fingers to release, one finger placed on each of the two opposing sides of the buckle. It is not directly applicable for adaptation as a connector in a folding boat. At times connectors in large mechanical objects such as folding canoes need more than the human hands to disengage the locking mechanisms due to mechanical stresses which may tend to unavoidably bind or restrict the connection in some way. For example, as a matter of reality and practicality in a field situation, a tool, such as the end of a pointed wooden sapling, may be needed in such cases to a release the locking mechanism. This would be difficult-to-impossible using the Suk-type releasing mechanism. Also the positioning of the releasing mechanisms in opposition to each other may inhibit access to the unlocking mechanism because of purely physical positioning reasons. both of the locking mechanism on the fastener, and because of the location of the fastener within the skeleton of a folding boat.
The car-seat belt buckle, disclosed in U.S. Pat. No. 4,502,194, operates with a different locking mechanism than the buckle cited above. It contains a spring which would be subject to binding and seizing, due to invasion of sand or other debris into the locking mechanism, if implemented in a canoe which is continually subjected to the elements of water, weather and debris.
A connector system for construction of roofs, disclosed in U.S. Pat. No. 381,137 for connecting purlin and rafters to roofing requires solid rigid bolt as a securing device. A clamping device disclosed in U.S. Patent No. 1,920,130 for clamping together pipes, rods, cables, ropes and for other purposes requires a retaining screw to secure. A retaining clip, disclosed in U.S. Pat. No. 3,004,370, for right angle connections, requires sheet metal for its construction, and its action depends on teeth present on the jaws of the device to flex then return with biting, a clamping action which damages the target member. A connecting clip for joining concrete reinforcing rods, disclosed in U.S. Pat. No. 4,110,951, is not adjustable for various retaining angles, i.e., various angles of repose. A pipe clasper, disclosed in U.S. Pat. No. 3,932,049, is not itself securable in position on its mounting member. None of the preceding connectors allows for a wide variety of connecting angles, and, in general, all are meant to remain permanently in position once installed. This does not suit the purposes of a collapsible portable watercraft.
A folding Dinghy, as disclosed in U.S. Pat. No. 4,124, 910, folds but doesn't disassemble.
It is an object of the present invention to overcome the disadvantages of the prior art and provide a collapsible canoe or folding boat that has an enhanced rigidity that is fully adjustable, thereby providing performance more typical of a non-collapsible watercraft.
It is also the object off this invention to provide, in connection with the preparation of a folding boat, a structural configuration which allows for said rigidity, while at the same time providing ease of construction and assembly, in a substantially portable configuration.
It is also a specific object of the invention to provide the enhanced structural integrity in a folding boat by incorporation of a novel boat skeleton, optionally in the presence of an antiflex air-bladder system and/or attached floor.
It is also a specific object of the invention to provide enhanced resistance to longitudinal hull flex by incorporation of antiflex air-bladder system and optionally by novel boat skeleton elements in the presence or absence of said antiflex air-bladder system.
The present invention describes structure and methodology to build a variety of flexible-hulled folding boats such as open canoes, kayaks, bull boats, dinghies, and rowboats. Such craft, among many others, are included within the scope of this invention. The present invention is a set of individual improvements, such when present together, give a synergistic overall effect sufficient to place a boat made from this technology into a new generation of folding boats. The ease of extension of this technology to folding boats other than canoes, gives the totality of these improvements the characteristics of a design system. The basic embodiment discussed is a canoe. The shape of the present basic embodiment of the invention is typical of many modem canoes of a popular design and can best illustrate the implementation of a specific design using the system. However, radically different alternate embodiments are briefly described later in the section on scope-of-the-invention to illustrate the breadth of the potential applications of the system. These alternate embodiments include additional canoe designs and other types of watercraft.
The advancements and improvements of the present invention over prior art in a basic embodiment of a folding canoe are as follows:
1. Antiflex Air-bladder System.
The implementation of the air-bladder with cover system as per the present invention functions most importantly to add a variable amount of additional stiffening to the hull of the canoe. This has not been successfully addressed in any of the prior art kayaks and canoes and is a great improvement over prior art. It also has the benefit, present in most air-bladder or sponson prior art designs of making the canoe much easier to assemble and disassemble. The air-bladders are inflated after the skeleton and skin are assembled thus bringing the skin into tension and snugging it against the already assembled skeleton.
The amount of flex in the hull can be adjusted by the amount of stiffening introduced by controlling the air pressure in the air-bladders. A solo paddler in white water rapids might want less stiffening to increase maneuverability. A pair of tandem paddlers in the same boat might want higher air pressure with its increased hull stiffening to counteract the tendency of the ends of the canoe to sink deeper in the water under the action of their weight and their position at the ends of the canoe.
The air-bladder, as side-flotation, provides for greatly increased stability when swamped with water, which helps maintain the paddler in controlling the canoe, thereby diminishing the likelihood of capsize and extending the opportunity to get to safety with the craft. It provides for enhanced recovery capability in a near capsize situation when a gunwale has dipped below the surface of the water, because the flotation along the sides of the canoe, now being under and surrounded by water, tends to force the gunwale back toward the surface.
Contrary to the claims of some folding kayak companies the flotation in the sides of a kayak, the sponsons, do not reduce the likelihood of capsize when no water is present in the kayak. In a upright kayak, side sponsons add stability when the craft is water laden, as it does in a canoe. However, it is no less likely to capsize, than a kayak without sponsons which has the same outer hull shape and dimensions, as the kayak with sponsons. The gunwale on a kayak is essentially the cockpit rim. Hence, it is evident that a kayak has already capsized if its cockpit rim has dipped below the level of the water. Then it's too late for side sponsons to prevent capsize.
The antiflex cover provides the key function of anchoring the air-bladder to the hull skin to aid in the transfer of the stiffness of the air-bladder to the hull of the canoe; and it offers protection to the air-bladders from trapped debris and water. It also protects it from the sun's ultraviolet light, from abrasion, and from air-leakage from small punctures. It thus prolongs the life of the bladders. It eliminates inconveniences for the paddler since water and debris have no place to collect to require cleaning while afield. The removable air-bladders are easy to repair in the field with minimal repair materials.
Although the side stringers are not directly part of the antiflex system, they are of importance in helping hold the antiflex-system in the proper orientation for maximum effectiveness. This allows the antiflex system to have its greatest impact at reducing hull flex. The side stringers thus play a dual role since they also directly improve the structural rigidity of the isoskeleton itself.
The air-bladder assists in giving superior structural strength to the canoe in pin and broach situations and makes it likelier that the canoe will be rescued rather than destroyed.
2. The Isoskeleton and its Building Blocks.
If an air-bladder were to be punctured, the tension in the skin, which is the securing means for holding the gunwales to the formers, would be released. Due to the design of the prior art connectors, the former then would be subject to lateral stress which could dislodge the two mating elements of the connector since there is no laterally locking action on this type of connector. This can happen, even with the skin still in tension, in prior art.
A solution to the problem of formers disconnecting from the stringers, due to inadequately locking connectors, is to modify the existing connector design in order to give a more secure, though not isotropically secure, connection. For example, simply enhancing the same style of connector employed to latch more firmly without significantly altering the overall shape or mechanism for locking action. This might suffice to prevent the formers from accidentally being dislodged from a stringer by a paddler's foot inadvertently pressing against it, one of the main causes of unintended disconnection in prior art canoes; but, it would not solve the problem of a lack of overall isotropic skeletal security in mechanically stressful circumstances. Any approach, short of locking the formers to both the gunwales and the stringers with isotropic security, is inadequate to solve the structural integrity problem.
The elements of the present invention solve both the problems described above. The isoconnectors, and lockconnectors, provide both rotationally and translationally secure connections. Taken together with the gunwale terminator fasteners, they provide the means whereby the skeleton achieves structural integrity and isotropic security over prior art folding canoes. They do not rely on the hull skin to maintain the structural integrity of the skeleton. The isoconnectors provide for isotropically secure locking of formers to stringers. The lockconnectors assure that the gunwales remain locked to the formers, and the gunwale terminators and fasteners assure that the stems are locked securely to the gunwales. With these improvements state of the art is advanced to isotropically secure skeletons.
This is of key importance in the event a side air bladder becomes deflated from puncture. Flat air-bladders won't cause the skeleton to disassemble in the canoe constructed per the present invention. If the air-bladders both become punctured when the canoe is out on a choppy ocean with no hope of reaching shore any time soon, or in the middle of a long rapid on a large river, the paddler can be assured that the canoe will continue to retain its skeletal integrity and can continue to be paddled until safe haven is reached for repair. An isotropically secure skeleton is also important if the canoe becomes pinned or broached on an obstacle in a current. It eliminates the likelihood that the boat will disassemble in situations short of the outright fracture of the members themselves. This can spell the difference between a destroyed canoe and a salvaged canoe, and likewise a salvaged trip, and perhaps even salvaged personal safety. A structurally secure skeleton gives superior strength in such circumstances compared to prior art. All of these above concerns are met in the present invention.
Relative to prior art, the gunwale terminator design, method and position of fastening, and integration with the gunwales themselves enhances the esthetic appearance, as well as the structural integrity of the canoe, has fewer parts, and permits faster assembly of the canoe by the user. Solid terminators, integral with the gunwale, give breadth and flare to the bow and stern sections, increasing seaworthiness and ability to ride the waves with a reduced possibility of swamping. Solid terminators, integral with mid-stem mounted side-stringers, enhance the whitewater capability of a canoe by adding a controllable amount of flare to increase seaworthiness beyond that added by the gunwale terminators. Thus versatility in designing the bow and stern sections of the canoe is created in the present invention, which is missing in the prior art. The solid, rigid gunwale and side-stringer terminators enhance overall canoe rigidity when in use and when in capsize situations. The locking isoconnectors and lockconnectors make the canoe easier to assemble, since the locked parts do not slip back out of place while other parts of the boat are being assembled. This is a major problem in the prior art.
The isoconnector of the present design is closely related to prior art, but consists of fewer parts and is of a simpler design. It provides connecting functions in a different fashion, requiring one finger, rather than two, for release of the connection. This is an important consideration, when hands and fingers are too cold to function properly as might be true on many northern rivers. The flanges on the side of the male isoconnector serve a dual role of protecting the locking tab from fracture during transport and handling when not in the connected state, a further advantage over prior art.
When a former is being installed in the canoe, the channels on the male isoconnector comprise self-alignment guides for connecting with the female isoconnector. This simplifies and speeds water-side assembly for the user. These self-aligning isoconnectors also speed the stringers into the properly spaced-apart positions from each other. The self-alignment channels help retain the stringers in place after canoe assembly, an additional skeletal security feature. The flush face on both the male and the female isoconnector parts simplifies initial installation onto the stringers and formers by aligning with each other on a flat horizontal work surface. This saves initial assembly costs compared to prior art. The spacers and shockcords reduce the number of parts required when connecting stringers together and speeds the initial assembly of the stringers at the factory, both of which reduce manufacturing costs. The wing fasteners which connect the floor and the chine stringers to the stem have fewer parts than the prior art. A further advantage over prior art is that no tools are required for assembly of the canoe by the user.
The universal grasp connector of the present invention provides additional function and more versatility than prior art by being portable, adjustable, and by allowing a variety of connection configurations and connection angles to be realized.
3. Shockfloor.
One particular improvement to the hull skin over prior art, is attachment of the foam to the floor fabric of the canoe. Using a higher density foam than that used in prior art assures less permanent distortion of the foam by the stringers, and thereby assures a continued snug fit. Water will not get under foam to make the canoe heavy and unwieldy, as occurs in prior art folding canoes.
4. The Assembled Canoe and Handling Performance.
Some remarkable safety features are built into the canoe of the present invention. The task of recovering a canoe in a capsize situation is highly simplified by the high amount of lighter-than-water side-flotation present. When retrieving the canoe, turning it on its side creates a self-bailing situation in which the air-bladder in the side of the canoe, which is under water, forces the canoe toward the surface, emptying water as it rises. Then simply flipping the canoe upright yields a canoe nearly empty of water. This same feature also makes it easy and safer to accomplish a mid-stream re-entry of the canoe by a swimmer. Recovery from impending capsizes is improved by side-flotation. A new level of stability is introduced which transcends secondary stability since the chance to recover continues after the gunwale dips below the surface.
The flexible outer skin of the canoe and particularly the shock absorption provided by the air-bladder in the sides of the canoe allows the canoe to absorb more shock and impact from collisions with obstacles and from waves in turbulent water than hard-hulled canoes. The paddler of the soft-hulled canoe is better able to maintain control of the craft because of the reduction of the violent jarring action which is more emphasized in a hard-hulled boat. The soft-hulled craft handles more smoothly in violent water.
The shape of the bow provided by the gunwale terminator and side stringer terminator designs allow for designing broader bow and stern areas of the boat which creates more lift at the ends of the boat for surmounting waves. Enhanced skeletal rigidity, as distinguished from hull material softness, aids in canoe maneuverability and overall strength in a synergistic fashion when taken together with the antiflex-air-bladder system and the other elements of the skeleton in the canoe. Thus, with soft-hulled canoes and less hull flex, the average paddler finds an optimal trade-off with regard to boat manageability.
As a result of its lightness along with all of the above reasons, the characteristics of the canoe make it safer than prior art folding canoes and safer than hard-hulled canoes faced with similar circumstances of class of water, skill level of paddler, prevailing weather, level of safety precautions taken, and water turbulence, among other considerations. A paddler in control of his canoe is almost always safer than when out of control or when swimming a rapid. Running whitewater in any boat design entails risks to the occupants that no boat design can eliminate. However the canoe of the present invention enhances the chance that the paddler will remain in control of the canoe. Finally, the side flotation enhances ability to side-surf which constitutes a performance improvement and enhanced recreational capability.
5. Development of New Boat Models Using All or Parts of the Invention
Each of the sub-systems of the present invention are useful in designing alternate embodiments of boats. The various connectors and fasteners and their alternate embodiments taken together comprise a complete system of connectors and fasteners for fashioning a wide variety of hull shapes and forms and skeletal configurations.
In implementing the antiflex air-bladder system, the number of air chambers, and their lengths and diameters can be varied. Combined with some flexibility with their positioning in the boat, greater versatility is gained in modifying the shape of the hull of the boat. Alternate embodiments are easy to create by changing the shape of the stems, by where the various stringers are fastened to a stem, by the modifying the width of the gunwale and side stringer terminators, and by the number of stringers and formers used and by their locations. Some of the elements such as the stem may be absent, or a true keel may be absent, from alternate embodiments as in a bull boat. Some designs may have more than one keel such as in an alternate embodiment of a canoe to obtain a wider bottom.
The system provides an eloquent way to speed development of designs of new models from this technology, by enabling a skeleton to be connected piece by piece, while modifications are made to other parts of the emerging skeleton. The various embodiments of a strap fastener provides a means to rapidly adjust the position of a side stringer or other skeletal members. By raising or lowering the wings of a wing fastener, a means to alter the shape of keel line of the boat obtains by varying the elevation of floor or chine stringers above the floor of the canoe.
The grasp fastener breaks the restriction of requiring at least a 90 degree angle between two connected members, thereby allowing greater versatility in fastening configurations and broadening the range of skeletal structures possible.
In any boat designed with this system: The shockfloor may not be present or the shockfloor foam laminate may be located elsewhere in the boat than in the floor; the antiflex system may be present only in part or in total; a greater, or a lesser number of stringers may be present to create a wider, or a narrower or a deeper canoe; the relative positions and orientations of the stringers to each other may vary; the arrangement of attachments of formers to stringers, particularly at the ends of the canoe may vary; a greater, or a fewer number of formers and a varying number of thwarts may be present; a thwart or thwarts may be attached directly to the gunwales; a side stringer may not be present or additional ones may be present; lockconnectors may be replaced by isoconnectors; the stem may be absent as per the example of the bull boat, and in which the stringers close on themselves; in cases such as the dory, illustrated later in the section on the scope of the invention, the stringers may actually cross over each other to gain the desired hull shape and to provide less hull flex.
One major advantage of the elements and methodology of the invention and is that one does not rely on intermediate steps such as expensive molds or plugs which are necessary, for example, for constructing fiberglass plastic or hard-hulled laminated-skinned canoes. The development progresses directly from the design on paper to the building of the boat itself. The system can be used to rapidly develop prototype hull shapes at minimal expense, for building either folding boats or for prototypes to be cast ultimately in fiberglass, plastic, metal or other material. The cost of the tools to do the bending of the skeletal structures, and to do the sewing of the fabrics to create the skin, are all relatively low. The connectors to connect the elements of the skeletal structure are relatively low cost.